With each side having netted five spot-kicks, Langfield denied Michael Doyle before Mark Reynolds stepped up to rattle his effort past Scott Bain and secure passage. "All the penalties were good and Langfield made a great save," said Paul Hartley, the Alloa Athletic manager. "Sometimes there's a hero and a villain."
Given the Pittodrie side's recent cup history, including the embarrassment of being eliminated by Dunfermline Athletic, Raith Rovers and East Fife, the tension around the ground was thick, particularly as this was the return of Hartley. The former Aberdeen and Scotland player has lead Alloa to consecutive promotions and brought them north with a well-considered game plan. Alloa deployed a defensive position as the hosts dominated and showed few signs of panic, not even when Peter Pawlett's long-range volley stung Bain's hands as he touched it over.
However Aberdeen's inability to capitalise on their domination was of considerable concern to their management team as the visitors began to enjoy more time on the ball. Indeed, had Langfield not saved Darryl Meggatt's firm header, and Stephen Simmons not made a mess of one early second-half opportunity from 12 yards, they might have taken the lead.
If that was a worrying moment for McInnes, however, what appeared to be a bad injury to Jonny Hayes caused disquiet. The Irishman's head clash with Meggatt was sickening and, after several minutes of treatment, he was stretchered off. Willo Flood also left the field injured.
Meantime, the SPFL Championship side grew in confidence, perhaps recognising that, for all their time on the ball, Aberdeen were power-puff up front. They were given a warning, though, in the opening moments of extra time when Nicky Low, on loan at Recreation Park last season, cracked a drive against Bain's knees.
Before that stage was reached, the already meagre crowd of less than 5000 had diminished as disappointed fans made their way home after watching the visitors test their team too many times towards the close of regulation time. They missed a frantic shoot-out but one in which their side would eventually prevail. "The quality of the penalties was fantastic for both sides, and their boy was really unlucky," said a relived McInnes.